Washington (CNN) - The Senate on Thursday is expected vote on a "resolution of disapproval" by an Alaskan senator that would prevent the Environmental Protection Agency from further regulating air pollution from vehicles and industrial facilities.

Alaska Sen. Lisa Murkowski, the author of the resolution, vowed Tuesday to strip the EPA of its authority to impose new limits on the emission of greenhouse gases.

Murkowski has the bipartisan support of 40 other senators, who may disagree with each other on the scientific impact of greenhouse gases, but who all agree that such regulations should be authorized by Congress, not an executive agency.

"The EPA intends to take control of climate policy, take it away from the Congress," Murkowski said at a press conference with 11 of her fellow Republican senators. "And I think those that are looking at this from the perspective of separate but equal branches of government look at this and say that this is absolutely unacceptable."

It is unclear whether there is enough support in the Senate to approve the measure, but its prospects in the House are slim.

Alaska Sen. Lisa Murkowski vowed Tuesday to strip the Environmental Protection Agency of its authority to impose new limits on the emission of greenhouse gases.

Washington (CNN) - Alaska Sen. Lisa Murkowski vowed Tuesday to strip the Environmental Protection Agency of its authority to impose new limits on the emission of greenhouse gases.

The Senate on Thursday is expected vote on a "resolution of disapproval" by Murkowski that would prevent the EPA from further regulating air pollution from vehicles and industrial facilities.

Murkowski has the bipartisan support of 40 other senators, who may disagree with each other on the scientific impact of greenhouse gases, but who all agree that such regulations should be authorized by Congress, not an executive agency.

"The EPA intends to take control of climate policy, take it away from the Congress," Murkowski said at a press conference with eleven of her fellow Republican senators. "And I think those that are looking at this from the perspective of separate but equal branches of government look at this and say that this is absolutely unacceptable."

It is unclear whether there is enough support in the Senate to approve the measure, but its prospects in the House are slim. Regardless, the White House on Tuesday issued a veto threat if it makes it to President Obama's desk.

EPA administrator Lisa Jackson said Friday there is a chance that workers will be able to stop the flow of oil into the Gulf of Mexico.

(CNN) - EPA administrator Lisa Jackson said Friday there is a chance that workers will be able to stop the flow of oil into the Gulf of Mexico, but warned that the EPA is preparing for the worst.

"There is still the opportunity and the possibility that they would be able to shut it down," Jackson told CNN Chief National Correspondent John King. "Of course as responders we have to look at the worst case, and keep planning for that."

Jackson's comments come as the federal government is ramping up the pressure on BP to do more to stop well leaks gushing thousands of barrels of oil into waters off Louisiana. The government is also pushing BP to beef up its response as a giant oil slick approaches the Louisiana coast.

The anticipated announcement by EPA administrator Lisa Jackson stems from a Supreme Court ruling which ordered the agency to determine the impact of carbon emissions not only on the environment, but on public health.

Immediately after the announcement, Jackson will head to Copenhagen, Denmark, to participate in the Copenhagen Climate Conference ahead of President Barack Obama's appearance on Friday.

Her statement could provide proof to the conference that the agency and the Obama administration are taking global warming seriously. However, White House aides caution the finding does not mean the EPA will immediately begin regulating industries that pollute the air.FULL POST

WASHINGTON (CNN) - In a hallway lined with portraits of her predecessors, Lisa Jackson is reminded daily of her unique status - as the first African-American to head up the Environmental Protection Agency.

"I don't think of it every moment. ... [But] what I hope that we see at the end of this are activists who look like me - activists who represent the future demographic of our country because that's who's going to be the EPA in the future."

And walking the halls also brings forth a sentimental feeling.

Jackson's father was a postal carrier - one of the few jobs she says was available to African-American men in the South when she was growing up. He died when she was a teenager, and she's reminded of him often when she's at work. The building housing EPA headquarters originally was built for the then-U.S. Department of Post Office in the 1930s.

But it's also her background as a mother, graduate from Princeton and Tulane universities and an African-American from New Orleans' 9th Ward that she says allows her to tackle the issues facing the environment.

As Hurricane Katrina battered the vulnerable Louisiana city in 2005, Jackson was on the verge of a career change: New Jersey Gov. Jon Corzine asked her to head up the state's Department of Environmental Protection. She says it was a hard choice because Katrina destroyed more than just her family's home - it destroyed the entire community.

Michelle Obama spoke to roughly 1,000 EPA staffers, her latest stop in a series of visits to government agencies, thanking employees for their work and assuring them that they have 'unwavering support from a phenomenal president.'

(CNN) – "We now have a president who's going to put science at the heart of our environmental policies and decisions," Michelle Obama said to a cheering crowd of employees at the Environmental Protection Agency Thursday. "It's a new day."

Mrs. Obama spoke to roughly 1,000 EPA staffers, her latest stop in a series of visits to government agencies, thanking employees for their work and assuring them that they have "unwavering support from a phenomenal president."

"This new era puts the EPA at the center of President Obama's highest priorities, securing America's energy independence and securing the future of our planet by combating climate change," the first lady said.

The EPA is an agency whose mission is particularly close to Obama's heart: public health. "I've often spoken about my most important job - being a mom, and like mothers and fathers everywhere, the health and safety of our children is our top priority," she said. "This is what it is all about - the future."